Coupling for hoses and similar conduits

Abstract

A connection at which two hoses or similar conduits are coupled includes a male coupling on one of the hoses and a female coupling on the other hose. The male coupling consists of a body that receives the hose and a tapered bushing which threads into the hose and spreads it outwardly into the body. The body has a threaded end section. The female coupling consists of a threaded ring having an inwardly opening groove, a ferrule that receives the hose and has at its one end a flange which fits into the groove of the ring, and a tapered bushing that threads into the hose and expands it against the ferrule. When the hose and bushing are out of the ferrule, the flange of the ferrule will fit into the ring, but when the hose is expanded outwardly by the bushing, the flange of the ferrule is captured in the groove of the ring. The ring threads over the threaded end section of the male coupling and forces the ends of the threaded section and the ferrule together. Since both the body of the male coupling and the ferrule of the female coupling are formed from a somewhat flexible material, an extremely good seal is created at the area of abutment. The end of the ring also abuts against a shoulder on the body of the male coupling, while the ring along the side wall of its groove bears tightly against the flange on the ferrule of the female coupling, forming very secure seals at these locations also. This redundancy of seals renders the connection virtually leakproof.

What is claimed is: 
     
       1. In combination with first and second conduits, such as hoses, a connection for joining the conduits at their ends, said connection comprising: a first flexible body fitted over the first conduit, the first flexible body being formed from a plastics and having at one end a threaded section provided with external threads; a first bushing fitted into the end of the first conduit such that the first conduit is spread outwardly and bears against the first flexible body, forming a fluid-tight seal therewith, the first bushing being made from a material that is substantially harder and less flexible than the material from which the first flexible body is formed; a second flexible body fitted over the second conduit and also being formed from a plastics; a second bushing fitted into the end of the second conduit such that the second conduit is spread outwardly and bears against the second flexible body, forming a fluid-tight seal therewith, the second bushing being made from a material that is substantially harder and less flexible than the material from which the second flexible body is formed; and a ring engaged with the second flexible body such that it can rotate on the second flexible body but is confined axially on that body, the ring having internal threads for engaging the external threads on the threaded section of the first flexible body and drawing the two flexible bodies into abutting engagement with one another and fluid-tight contact. 
     
     
       2. The combination according to claim 1 wherein the inside diameter of the first bushing is generally no less than the inside diameter of the first conduit beyond the connection and the inside diameter of the second bushing is generally no less than the inside diameter of the second conduit beyond the connection. 
     
     
       3. The combination according to claim 1 wherein the second flexible body has a flange that projects outwardly and the ring has a groove that receives the flange; and wherein the flange will fit into and can be withdrawn from the ring when the second bushing and second conduit are detached from the second flexible body. 
     
     
       4. The combination according to claim 1 wherein the first flexible body has a shoulder located at the end of the threaded section and the ring on the second flexible body has at its end an abutment face which abuts against the shoulder on the first flexible body when the ring draws the two bodies together such that the threaded end section on the first flexible body is against the end of the second flexible body. 
     
     
       5. The combination of claim 1 wherein the first flexible body also has an intermediate section which is located between its ferrule and the threaded end portion; and wherein the first bushing expands the first hose into the intermediate section. 
     
     
       6. The combination according to claim 1 wherein the bushings externally have a tapered leading portion and an enlarged trailing portion; wherein a thread spirals around the two portions; and wherein the enlarged portion is further provided with a circumferential rib which projects outwardly therefrom. 
     
     
       7. A female coupling for a hose or similar conduit, said coupling comprising: a ring having internal threads and an inwardly opening groove; a ferrule fitted at one end into the ring and being sized internally to receive the hose, the ferrule being formed from a material that is somewhat flexible so that the ferrule can be distorted, the ferrule at said one end having a flange which normally projects into the groove of the ring to retain the ring on the ferrule, the flange being flexible enough and small enough to be inserted into the ring and engaged with the groove of the ring when the ferrule is not rigidified from within; and a tapered bushing sized to fit into the end of the hose and having an external thread to enable the bushing to be threaded into the hose when the hose is within the ferrule, so that the hose is expanded against the ferrule, the bushing being sufficiently rigid to further, upon being threaded into the hose, expand and rigidify the resilient ferrule at its flange, with the expansion being great enough to project the flange into the groove of the ring and prevent the ring from being removed from the ferrule. 
     
     
       8. A coupling according to claim 7 in combination with a hose that fits into the ferrule; and wherein the inside diameter of the bushing is generally no less than the inside diameter of the hose beyond the coupling. 
     
     
       9. A coupling according to claim 7 wherein the bushing externally has a leading tapered section and a trailing enlarged section, both of which have the thread spiralled around them; and wherein the enlarged section is provided with a circumferential rib that projects radially outwardly and is convex in cross-section. 
     
     
       10. A male coupling for a hose or similar conduit, said coupling comprising: a body formed from a somewhat flexible material and having a ferrule at one end, an end section at the other end, and an intermediate section between the ferrule and the end section, the ferrule having a bore adapted to receive a hose, the intermediate section being larger in terms of radius than the ferrule or the end section, the intermediate section further containing a tapered surface and an annular recess with the tapered surface flaring outwardly from the bore and terminating at the recess which opens inwardly and is larger in diameter than the large end of the tapered surface, the end section having external threads and a bore that extends from the recess to the end of the body but is smaller in diameter than the recess; and a tapered bushing sized to fit through the bore in the end section and into the end of the hose and having an external thread to enable the bushing to be threaded into the hose, the bushing being sufficiently rigid to expand the hose outwardly into snug contact with the tapered surface of the body and also having a rib that locates opposite the recess when the bushing is fully inserted into the hose with the rib being large enough to expand the hose into the recess. 
     
     
       11. A coupling according to claim 10 wherein the intermediate section of the body has a shoulder and the threaded end portion projects from the shoulder.